Nanoparticle assisted Raman information acquisition from metal encapsulated sandwich structure

For the induced image charge on surface, the metal film as a substrate brings the metal nanostructures some novel surface plasmon‐related phenomenon, e.g. electromagnetic field redistribution and energy focusing. In this work, the surface‐enhanced Raman scattering in sandwich structure consist of Au nanoplate and Au film adsorbed with molecule monolayer is investigated. The surface‐enhanced Raman scattering spectra point out that the shielded Raman signals of molecule under metal nanoplate could be collected from this metal‐encapsulated sandwich structure with the help of nanoparticle. This interesting phenomenon is further confirmed by the simulated electromagnetic field where the light power in the gap between Au nanoplate and Au film is greatly enhanced with a nanoparticle located. The further results also demonstrate this nanoparticle assisted Raman information acquisition is highly influenced by the thickness of encapsulated nanoplate and size of nanoparticle. Furthermore, the positive results of nanoparticles with different shapes in this interesting phenomenon provide an extensive application prospects including surface‐enhanced Raman scattering detection, light information storage and selective harvesting, location detection of light information, photocatalysis, etc. Copyright © 2016 John Wiley & Sons, Ltd.